63_Trying to start after lower end bearings replace

[Steve D.]

Sorry, but I have the classic whine of "I've done everything right, but it still won't start". The distributor is indexed properly with the rotor at #1 with #1 cylinder at TDC of compression stroke. Solid lifters lash set with the Williams-Hinckley procedure. Verified that spark is getting to the new plugs. The battery is good and turns the engine over easily. I prime the carburetor with a bit of gas and crank, but the prime gas does not fire. I have rotated the distributor while cranking, but with no luck. I spent some time in the archives, but haven't found the answer. I don't think the fuel pump has filled the carburetor bowls yet, but since the prime gas is not firing off, I assume I have another problem. Any help for the helpless?

Steve

[Russ S.]

Re: 63_Trying to start after lower end bearings replace

Are you sure you are TDC on compression stroke and not TDC on exhaust stroke?

[Tim E.]

Re: 63_Trying to start after lower end bearings replace

Steve - Sorry to hear you're having trouble getting the engine running again. How much of the top end of the engine did you have apart to replace bearings....did you remove heads, timing gears/chain, intake manifold? I assume you had these parts off the engine.

Can you run a compression check? Good compression (> 90) will indicate that the valve train is properly timed with the crankshaft. If that checks out OK, your air/fuel mixture could become unburnable (far too lean) if there is a serious air leak at the intake manifold gaskets or the gasket between the carb and the intake.

Since you can't get the engine to fire on prime gas, it makes me think that either there is no (or not enough) compression or the mixture has been compromised between the carb and the combustion chamber. Tim

[Timothy B.]

Re: 63_Trying to start after lower end bearings replace

Make sure you have a fire extinguisher close by. I would recheck the cap/wire position, are you using points?

[Frank D.]

Re: 63_Trying to start after lower end bearings replace

Priming down the carb's throat eliminates about 90% of typical fuel deliver problems.

Check for spark at the plugs; easy enough to hold a plug wire (wear gloves) near a ground while cranking and look for a fat blue spark.
Then check that the points are actually opening, and, at the right time...

[Harry S.]

Re: 63_Trying to start after lower end bearings replace

As a test, bypass the ballast resistor. If it starts the ballast resistor is bad.

[Frank D.]

Re: 63_Trying to start after lower end bearings replace

You can actually run a jumper wire from the "+" battery terminal to the "+" ignition coil terminal (TEMPORARILY) and eliminate a slew of wiring along with the ignition switch, ballast resistor, what-have-you. You can then narrow things down from there if the car starts...

[Steve D.]

Re: 63_Trying to start after lower end bearings replace

Thanks everyone_ here is a collective reply

TDC _ I have double checked; both #1 valves are closed when the rotor is in #1 position

Engine was completely disassembled. I have not checked the compression, but I degreed the cam when I re-installed it, and matched the cam specs. I will check the compression.

Fire extinguisher close at hand. I have checked the cap and wires, the position of the wires on the cap, and checked to make sure the right wire is on the right plug. I do not have points; I have a Pertronix ignitor.

I checked for spark at several plugs and all looked well.

I have not checked the ballast resistor. I will bypass it and see what happens.


Thanks for your input. I will report back this evening.

[Tim E.]

Re: 63_Trying to start after lower end bearings replace

Steve - Depending on the cam, both valves could be closed at TDC on both the compression and the exhaust strokes. With a valve cover off, bump over the engine and watch the intake valve on number 1.....when you reach TDC after the intake valve closes, the rotor should be pointing at #1. Another old trick I've used for an initial start: remove the #1 plug, put your finger in the plug hole, bump over the engine until your finger blows off the plug hole, point the rotor to #1, replace the plug, start the engine, and time it. Good luck, you've got some good ideas! Tim

[Frank D.]

Re: 63_Trying to start after lower end bearings replace

If you have the Pertronix Ignitor III (the version with the rev limiter) you MUST bypass the ballast resistor for it to operate properly...that unit wants a full 12V...

[Steve D.]

Re: 63_Trying to start after lower end bearings replace

Status report

I checked the TDC position with the #1 plug out (thumb test) and confirmed that the distributor is indexed on the compression stroke. I also checked the compression in #1 and got 120 lbs (domed pistons)

Tomorrow morning I will make sure the fuel line and carburetor bowls are filled, and try again.

Steve

[Tim E.]

Re: 63_Trying to start after lower end bearings replace

Steve - Good, that helps. A couple things come to mind next.

In an attempt to get the engine to at least pop and try to start, I'd try starting it on starting fluid next. You've mentioned a prime of gas, maybe you've already tried starting fluid. If the engine pops with fluid, that implies an incombustible mixture from the carb and or intake.

Plug or cap all vacuum ports on both the intake manifold and the carburetor first, including the vacuum advance. This will make sure there is not a vacuum leak upon start up.

At the other end of a mixture issue is flooding. You don't mention a smell of gas or the appearance of liquid fuel in the throat of the carb which usually exists with a flooding situation. Flooding could result from a problem inside the carb: leaking needle, missing parts, high float level, mismatched gaskets. If you can, disconnect and plug the fuel line from the tank to the pump (going into the pump). Also, disconnect the fuel line going into the carb (but be prepared to capture any residual fuel that squirts out from the fuel pump). Now, with no gasoline source...try to start the engine on starting fluid again.

This is kind of remote, but on the ignition side...a high compression engine does require a higher voltage spark. If you see a weak spark with a spark plug open to the atmosphere, it may be non-existent under a compression situation in the combustion chamber. Try a different 12-V coil to see if you can get the engine to pop.

You haven't mentioned this but also verify that the dwell angle of your points is 30 degrees.

Tim

[Gene M.]

Re: 63_Trying to start after lower end bearings replace

Steve,
You didn't say if you were getting spark to the plugs..... What does the timing light say?
Engine needs gas, air, spark and compression. Got gas and air check the other two.
Personally I would lose the Pertronix, another variable.

[Steve D.]

Re: 63_Trying to start after lower end bearings replace

Update _ got it started and runs fine.

After checking everything and still not even being able to fire the prime gas, I tried to think of what had changed from before the tear down: the only thing I could think of was that I had installed new plugs. So I removed the new plugs and installed the old ones, and behold_the prime gas fired off. (Checking those new plugs will be another exercise.) So I worked on the fuel delivery, got gas to the carburetor and it started up. The distributor was off a tooth, that was an easy adjustment. So all is well; uh...except the fuel pump is leaking. But that is part of the fun, right?

Thanks everybody.

[Joe M.]

Re: 63_Trying to start after lower end bearings replace

bad memories! took all the possible offending parts off and then back on and then off and then on.......by chance, eventually.......took out the champ uj12ys or was it uj12s, put in a set of accel plugs and it fired like a champ..... Wrong plugs!!!!!!!!!!! It happens.